Nothing special here. Don't laugh. But I need to share my joy.For some reasons the last time I tried undervolting my laptop's CPU, it didn't work. I must have done something wrong (didn't have any guide). I'm really glad I tried again.

I tried to "undervolt" my laptop's CPU 2 days ago and... Success ! My CPU "idle" (well, semi-idle...) temp went from 60-65C to 40-45C. A whopping 20C. It's super stable (tested it with Orthos, prime95 and just did a lot video rendering) and I don't feel like I'm slowly cooking my hands anymore...

Not only that, but I also gained some extra "battery life" and a barely audible fan.

I followed these 2 forum posts, mainly (plus a few other more technical articles). My first setup took me 1h30 total (reading the articles, setting the apps up, testing for 45 min.):

Glad I'm not just rehashing something dull and already too well known.

Undervolting is so safe that it should be tried if you have a bit of time...

I should add that after undervolting, I also dismantled my laptop and cleaned the ventilation system. This also helped bringing down the temperature upper limit my CPU was reaching when left at 100% for a while. Why ? simply because, when Idle the CPU doesn't need as much ventilation, but when used at max capacity it needs a good airflow to be cooled down, even if undervolted, of course. Dust was the second culprit in my case.

... the 1h30 to understand undervolting + 45min to clean my laptop was some well spent time.

Your mileage may vary... It seems that I'm lucky to have such a drastic reduction in temperature. A reduction of 8-10C seems to be pretty common though and it does make a "feelable" difference. Not to mention the slightly extended battery life (both in terms of "how long will I be able to work on single charge" and "how long will my battery lasts until I need a new one"... Since heat degrades batteries.) AND the noise reduction. This last aspect makes the operation interesting for desktop computers too.

Sorry to revive this old thread, but I just built a little Linux server here to have access to my archives from anywhere and stream media. Using Amahi with Ubuntu 12.04 : works really well, very stable, with a VPN, etc. A couple bumps on the road, but it was mostly my fault (didn't follow the steps carefully enough when I first entered my addresses from another laptop, etc.), but since I chose to do that on my old laptop (which comes with a free UPS... )... I was bound to have heat problems; that is because I changed he CPU a few years ago for something a but too powerful for the ventilation system it seems (?). On windows, I had to undervolt it, as mentioned above.

I almost thought I would be out of luck with Linux when the CPU hit 98 degrees 2 days ago... but , but... NO! there was a solution out there and I was able to once again successfully undervolt my T7500 using Linux PHC and following the steps on the 2 pages bellow. I used the voltages I previously used for Windows' RMClock. I actually dared to go even lower, successfully. If you're using Ubuntu and you follow the guide precisely, you shouldn't have any problems doing the same, unless your CPU isn't supported.

1- Make sure you're loading the right patched kernel (the PHC one). In the Ubuntu boot/Grub menu, you'll find it in "Previous Linux versions" I think. No PHC kernel = no undervolting.

Once you know the kernel seems to work properly, edit your /etc/default/grub file to load it as default. Using a GUI is probably the most intuitive and safe way to do it. Something like Grub Customizer. Install that (follow the steps in the previous link) and move the PHC kernel so that it becomes the 1st kernel entry)

3- to add phctray.sh as a startup app, it's easiest to just hit the "windows" key, type "startup", run the startup app, and then add /**your_path**/phctray.sh as a new item (fill the appropriate textbox)

4- Make sure that phctray (or phctool) is running. Use "System Monitor" (same as Task Manager) to check that out. if none of them are, your changed voltages won't be loaded. Something failed in the steps before.

5- You could double check that your voltages/multipliers are correctly saved in home/**YourUserName**/.phcstore.phc(you can actually even change the settings there, directly, if you know what you're doing)If you can't see the file, you might be hiding config files. Hit ctrl+h in Nautilus. Or change that in the preferences somewhere.

... anyway

You might run into other problems, but... I didn't. I actually only had to add the module to the modules file

A few hours of work (2-3) and it's so worth it. Amazing how cool this machine is running when under 100% load !